Function main

examples/tron.cpp:49–190

Main procedure ----------------

// Main procedure
//----------------
int main(int argc, char **argv) {

  // Print usage, help and retrieve command line options
  //-----------------------------------------------------
  cimg_usage("A very simple Tron game, using the CImg Library");
  cimg_help("--- Quick help ----------------------------\n"
            " Player 1 (blue) :\n"
            " Use keys 'Z' (up), 'S' (down), 'Q' (left)\n"
            "     and 'D' (right) to control your player.\n"
            "     Right 'CONTROL' key enables turbospeed\n"
            " Player 2 (red) : \n"
            "     Use arrow keys to control your player.\n"
            "     'TAB' key enables turbospeed.\n"
            "-------------------------------------------");

  const char *geom      = cimg_option("-g","300x300","Size of the game board");
  const int delay       = cimg_option("-s",10,"Game speed (lower value means faster)");
  const bool twoplayers = !cimg_option("-1",false,"One player only");
  const int zoom        = cimg_option("-z",1,"Zoom factor");
  const bool full       = cimg_option("-f",false,"Fullscreen mode");
  unsigned int W = 400, H = 400;
  std::sscanf(geom,"%u%*c%u",&W,&H);

  // Define game colors and variables
  //----------------------------------
  const unsigned char blue[] = { 128,200,255}, red[] = { 255,0,0 }, white[] = { 255,255,255 };
  int score1 = 0, score2 = 0, round_over = 0, ix1 = -1, iy1 = -1, x1 = 0, y1 = 0, u1 = 0, v1 = 0,
    ix2 = -1, iy2 = -1, x2 = 0, y2 = 0, u2 = 0, v2 = 0;
  bool start_round = true, turbo1 = false, turbo2 = false;

  // Create background image
  //--------------------------
  CImg<unsigned char> background, img;
  background.assign(64,64,1,3,0).noise(60).draw_plasma().resize(W,H).blur(2).normalize(0,128).
    draw_rectangle(0,0,W-1,H-1,white,1.0f,~0U);

  // Open display window
  //---------------------
  CImgDisplay disp(background,"* CImg-Tron *");
  if (zoom>1) disp.resize(-100*zoom,-100*zoom);
  if (full) disp.toggle_fullscreen().display(background);

  // Start main game loop
  //----------------------
  while (!disp.is_closed() && !disp.is_keyESC()) {

    // Init new game round if necessary
    //----------------------------------
    if (start_round) {

      // Init game variables
      round_over = 0;
      ix1 = -1; iy1 = -1; x1 = 10; y1 = 10; u1 = 1; v1 = 0; turbo1 = false;
      ix2 = -1; iy2 = -1; x2 = W - 11; y2 = H - 11; u2 = -1; v2 = 0; turbo2 = false;
      img = background;
      start_round = false;

      // Display a simple pre-round page